Lubricating oil



Patented Mar. 11, 1941 UNITED STATES PATENT osrlce or to Sun OilCompany, poration oi New Jersey Philadelphia, Pa., a cor- No Drawing.Application October 11, 1939, Serial No. 298,979

4 Claims.

My invention relates to lubricating oils and greases and comprises suchan oil or grease to which has been added a halogenated nitrile or ahalogenated nitrile-hydrocarbon mixture; I have succeeded in producingsuch halogenated. products from petroleum acids and paraffln wax and myinvention also comprises such products, which are useful for purposesother than as addition agents to lubricating oils and greases. Suchproducts are viscous oils, soluble in hydrocarbons in all proportions,having particularvalue as addition agents to lubricating oils intendedfor use under severe operating conditions, such as in hypoid gears. Thedifliculty with which such nitriles are hydroliz'ed makes themespecially valuable as lubricants, as they do not readily form corrosiveproducts as do the esters of the fatty acids. Owing to their stabilityagainst hydrolysis they may be added to greases without substantiallyaltering the alkalinity of the grease.

, The process of producing these products and the lubricating oil towhich they are added will first be described as applied to a mixture ofpetroleum acids and petroleum hydrocarbon as a starting material. Bypetroleum acids I intend to be understood as including such acids asusually occur in petroleum and particularly naphthenic acids which areformed or isolated during the refining process according to a number orpatents of the prior art, such as the patents to Hughes et al. No.2,056,913, Angstadt No. 2,013,619 and No. 1,931,880, or Alieman No.1,931,855, No. 1,694,461 and No. 1,694,463.

A mixture of such petroleum acids with petroleum hydrocarbons isdelivered to a reaction vessel made oi. glass, stainless steel, enameledlined metal or any other material that will not be at" tacked by theproducts to be reacted. Preferably the vessel is provided with a longnarrow neck or cylinder in order to provide for expansion andparticularly to aiford a longer period of contact between'the gas andthe liquid,

After the reaction vessel is loaded with the above mixture, it is heateduntil a temperature of from 200 C. to 400 0. (preferably about 350 C.)is attained. Ammonia is introduced at the bottom of the reactionchamber, preferably in a finely divided state, as, for example, througha tube provided with a diffusion plate; or a rotating stirrer, such as aturbo mixer, may be used.

At the top of the neck or cylinder provision is made for condensing andcollecting any water that is split olT, as well as any other materialwhich is volatile or is carried over by entrainment. A convenientarrangement includes a condenser provided with a water jacket. The wateris separated and the organic material returned to the reaction chamber.

The reaction may be carried on at atmospheric pressure, but if theboiling point of the starting material is below the desired reactiontemperature, a higher pressure is desirable. A pressure of about 75 lbs.per square inch is suificient in most cases. The reaction may be carriedout in the presence of dehydrating catalysts such as silica gel,alumina, thorium oxide, or like substances.

The reactions which take place between the petroleum acids and ammoniain forming nitriles involve three stages: firstthe formation of theammonium salt of the petroleum acids; second, splitting oil. water fromthis ammonium salt and forming the amide; and third, splittin off waterfrom the amide to form the nitrile. These stages may be represented asfollows:

(1) RLOOH NH: RCOONHi Petroleum acid Ammonia Ammonia salt of petroleumacids Water Amide of petroleum acids R.CO.NH2 heat H20 R.CN

Nitrilc of petroleum acids When water is no longer split oiT thereaction is complete.

Instead oi utilizing as a starting material a mixture oi petroleum acidsand petroleum hydrocarbons, oil-free petroleum acids may be used. Thesemay be separated from a mixture oi hydrocarbons and acids by any desiredmethod, such as by known methods of extraction with solvents. Or thehydrocarbons may be separated from the original mixture of hydrocarbonsand alkali metal soaps, as by known solvent extraction, and the soapsthen acidified. Purified petroleum acids having a saponification numberoi about 182.5 are produced by known methods and these may be used asthe starting material. Other petroleum acids having smallersaponification numbers and containing varying percentages oihydrocarbons are also produced by known methods and these also may beused as starting materials. For example, petroleum acids are known thathave a saponification number oi 130 and contain about 40% ofhydrocarbons. Any starting mixture of petroleum acids containinghydrocarbons should not contain over of hydrocarbons.

If purified petroleum acids are used as a starting material the ammoniatreatment above described is applied and the same reactions occur. Theresultant product is the same except that with one starting materialnitriles are formed and with the other starting material a mixture ofnitriles and petroleum hydrocarbons are formed.

Nitriles may also be produced, by the method above described, from amixture 01' unoxidized parafiin wax and oxidation products, preferably Ifrom a crude oxidation product of paraflin wax containing esters, acids,alcohols, other intermediate oxidation products and unoxidizedhydrocarbons, as set forth in an application filed by me October 11,1939, Serial No. 298,980. The nitriles thus formed may be separated fromthe hydrocarbons with solvents inwhich the nitriles are soluble and inwhich the hydrocarbons are nearly or quite insoluble. However, theremoval of the hydrocarbons is usually unnecessary. When nitriles areproduced from the crude oxidation product of paraffin wax they usuallycontain about 30% of unoxidized hydrocarbon.

Nitriles may also be formed from paraffin wax by simultaneously passingair, or other oxygencontaining gas, and ammonia through molten paraffinwax, as described in the application hereinbefore mentioned.

Preparatory to the next step the nitriles may or may not be purified byknown methods. Whether they are purified or not, and whether or not theyare in admixture with petroleum hydrocarbons, they are dissolved in asuitable inert solvent such as carbon tetrachloride and chlorine passedthrough the material until the desired amount of chlorine is taken up.The reaction vessel may be of essentially the same type as that used forthe preparation of the nitriles. The chlorine is introduced at thebottom of the reaction vessel in a fine state of subdivision, so thatthe reaction takes place rapidly. This may be done by a difiusor or astirring device such as a turbo mixer. The

temperature of the reaction mixture is kept below about 60 C. The use ofa solvent is desirable because the chlorinated nitriles are veryviscous, and it is diificult to get intimate contact between thepartially chlorinated nitrile and the chlorine. Any excess chlorine andhydrochloric acid may be removed by blowing the product with air, byheating under a vacuum, by washing with water, or by treating with aneutralizing agent such as quick-lime or sodium carbonate. Use of one ofthe latter two reagents removes some of the loosely bound halogen, andsuch treatment may be preferred when the product is to be subjected tohigh temperature conditions. If desired, the product may be treated withdecolorizing materials, such as filter clay, to improve the color.Usually it will sufiice, after the desired amount of chlorine isintroduced into the mixture, to remove the reaction product from thereaction vessel and wash it with water until neutral. The carbontetrachloride or other solvent is recovered by distillation. Thedistillation may be conducted under reduced pressure.

In the unsaturated nitriles the chlorine is largely taken up byaddition, whereas in the substantially saturated nitriles, such as thenitriles from the oxidation products of parafiln wax, the chlorine islargely taken up by substitution, hydrogen being split out of themolecule to form hydrogen chloride.

Where an exceptionally high chlorine content is desired, catalysts, suchas iodine or iron, should be used.

While it is uneconomical to utilize halogens other than chlorine, itwill be understood that nitriles embodying my invention may contain anyhalogen, namely, fluorine, bromine or iodine.

The amount of chlorine that may be introduced into the nitriles may varyfrom 5 to 50%, although it is rarely that it is desirable, for anypurpose, for the nitrile to contain less than or more than 45%.

The chlorinated nitrile may be added to lubricating oils in amountsvarying from .1% to 25%, the amount introduced depending upon thechlorine content of the nitrile and the purpose for which the lubricantis to be used. If the lubricant is to be used under severe operatingconditions, it is desirable to use a greater quantity of a chlorinatednitrile which contains a comparatively small amount of chlorine, such as10-20%. These compounds are more stable than the chlorinated nitrilescontaining the maximum amount of chlorine.

In claiming the addition of the chlorinated nitrile to lubricating oil Iintend that lubricating oil should have its broader signification andthereby include grease.

I do not herein specifically claim a halogenated nitrile ornitrile-hydrocarbon mixture derived from parafiin wax or from a mixtureof parafiin wax and its oxidation products, nor specifically thelubricating oil containing any of such products as an addition agent,nor the specific process of producing such lubricating oil, nor theprocess of producing such halogenated nitrile or halogenatednitrile-hydrocarbon mixture from paraffin wax; the same forming thesubject matter of another application for patent hereinbefore mentioned.

What I claim and desire to protect by Letters Patent is:

1. A lubricating oil to which has been added a minor percentage of anitrile, derived from petroleum and halogenated, containing over 5% andless than 50% of the halogen.

2. A lubricating oil to which has been added a minor percentage of anitrile, derived from petroleum acids and halogenated, containing over5% and less than 50% of the halogen.

.3. A lubricating oil to which has been added a minor percentage of ahalogenated nitrilepetroleum hydrocarbon mixture derived from petroleumand containing over 5% and less than 50% of the halogen.

4. A lubricating oil to which has been added a minor percentage of ahalogenated nitrilepetroleum hydrocarbon mixture derived from a mixtureof petroleum acids and petroleum hydrocarbons and containing over 5% andless than 50% of the halogen.

SAMUEL EDWARD JOLLY;

